Japanese Unexamined Utility Model Application Publication No. Hei 3-96954 describes in FIG. 5 an airbag in which, for sewing together a first fabric 1 and a second fabric 2 constituting the airbag, the first fabric 1 and the second fabric 2 are first sewed together with a first seam 4 while they are laid one on top of another with their edges 1a, 2a aligned, and then the second fabric 2 is folded back by 180° around the first seam 4 and the single-layer first fabric 1 and the double-layer second fabric 2 are sewed together with double-line second seams 5.
Besides, Japanese Patent Application Publication No. Hei 10-166978 describes in FIG. 2 an airbag in which a part where a passenger-side fabric 12, an inflator-side fabric 14, and an anti-gas leakage tape 30 of the airbag are laid in three layers is sewed at a circumference sewing section 16 formed by a chain stitch.